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Clojure 1.2.1/1.3/1.4 'proxy generated in Grails 2.0.0 runtime fails. 1.2.0 is fine
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edited Nov 21 '12 at 9:42
answered Nov 21 '12 at 9:07
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Determine the data types of a data frame's columns
...use ?str(). To explore some examples, let's make some data:
set.seed(3221) # this makes the example exactly reproducible
my.data <- data.frame(y=rnorm(5),
x1=c(1:5),
x2=c(TRUE, TRUE, FALSE, FALSE, FALSE),
X3=letters[1:5])
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What's the difference between “mod” and “remainder”?
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There is a difference between modulus and remainder. For example:
-21 mod 4 is 3 because -21 + 4 x 6 is 3.
But -21 divided by 4 gives -5 with a remainder of -1.
For positive values, there is no difference.
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C char array initialization
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answered Sep 8 '13 at 21:51
ouahouah
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SQL query to group by day
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answered Nov 1 '09 at 21:22
Anwar ChandraAnwar Chandra
7,94899 gold badges4141 silver badges6060 bronze badges
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Python using enumerate inside list comprehension
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edited May 27 '12 at 21:17
answered May 27 '12 at 21:05
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Stream.Seek(0, SeekOrigin.Begin) or Position = 0
...ekOrigin.Current?
– gonzobrains
Aug 21 '13 at 23:21
6
@gonzobrains "Return Value: The new positio...
Numpy: Divide each row by a vector element
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edited Nov 21 '19 at 16:13
answered Mar 21 '19 at 4:52
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Custom numeric format string to always display the sign
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edited May 24 '16 at 21:50
Craig
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answered D...
What does the constant 0.0039215689 represent?
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0.0039215689 is approximately equal to 1/255.
Seeing that this is OpenGL, performance is probably important. So it's probably safe to guess that this was done for performance reasons.
Multiplying by the reciprocal is faster than ...